First, thanks to everyone for all the information and education I've
received from BEEL over the past few months.

I would like to make a comment or two on the dark hive vs temperature
issue. The last thing I want to do is turn this into and infrared physics
class so I'll just hit the important points but there are some fundamental
properties of materials and their surface characteristics that determine
the amount of heat and the rate at which  objects absorb and reradiate
solar infrared radiation.

 All materials have an "emissivity rating" (between 0 and 1.0) which
indicates their ability to absorb, store and reradiate heat. Since we are
talking about opaque objects, 1.0 minus the  emissivity rating =
reflectance.  Wood, brick, stone, asphalt have high emissivity ratings
(0.9-0.96). They absorb most of the incident heat hold it a long time and
reradiate slowly. Shiny metals have low emissivity ratings (0.3-0.6) they
reflect most of the infrared radiation and cool very quickly. However the
emissivity (and the reflectance) of the material has more to do with
surface characteristics  than the bulk properties of the material itself. A
slick glossy surface on a pine board will have a lower emissivity (higher
reflectance) than a rough diffuse surface. The emissivity of a family of
paints will depend more on the sheen or gloss of the paint than the color.
A shiny glossy black paint can have a lower emissivity than a dull rough
white paint. If the surfaces are identical then the lighter paint will have
a little more infrared reflectance than the darker paint. White paint seems
much brighter to us than black paint only because we have visible light
sensitive eyeballs. If we could "see" in the infrared  region of the
spectrum, things would look much different.
 The ability of a surface to absorb heat also depends upon the angle of
incident radiation. (especially for a glossy surface). Another confusion
factor is that the emissivity and reflectance values are not constant
throughout the infrared spectrum.

So, where are we??

If the surface characteristics of the hive bodies are the same. i.e.
smoothness or "gloss",  then the whiter paint may have a slightly higher
infrared reflectance than the black paint, but I would guess only a few
percent.  On one extreme if we have a smooth glossy white surface and a
dull rough black surface then the effect may be greater. But the dark
painted hive, because of its' higher emissivity,  would TAKE LONGER to
reradiate its heat, cooling more slowly, not quicker,  than the white
painted hive.

The amount of heat absorbed by the hive is dependent upon total surface
area exposed to the sun.  Is one hive shading another?

Of course this aspect of hive heating does not even consider the complex
thermodynamic system of the colony itself which Bill Truesdell addresses.

Hope some of you are still awake after this.

Thanks,

bill vining
Huntsville, Alabama